Biology Topic 2

What is the organisation of cells

Cells, tissues, organ, organ system

What are enzymes

biological catalysts

What is the lock and key theory

Idea that an enzymes active site fits only one type of substrate.

What are the conditions needed for enzymes to work

Optimum PH optimum Temperature

What happens if conditions aren’t met for enzymes

They denature

What does carbohydrase break down

Simple sugars

What does protease break down

Proteins

What does lipase break down

Lipids(fats) into glycerol + fatty acids

What is small intestine function

Absorb small food

What is large intestine function

Absorbs water

What is pancreas function

Produces all 3 enzymes

What is the liver function

Produces bile which neutralises stomach acid

What is the gall bladder function

Stores bile

What is the rectum function

Stores indigestible food (faeces/poo)

What is the test for starch

Add iodine if present it turns from orange to blue/black

What is the test for proteins

Add biuret solution if present turns from blue to purple/lilac

What is the test for sugar

Add Benedicts solution if present turns from blue to brick-red

What is the test for lipids

Add Sudan 3 stain if present turns a red layer forms

What is the pathway of air in the lungs

Mouth/nose , trachea, Bronchi, Bronchioles, alveoli

What is gas exchange in the alveoli

When oxygen diffuses into blood carbon dioxide diffuses out

What does the left side of the heart do

Pumps oxygenated blood around the body

What does the right side of the heart do

Pumps deoxygenated blood to the lungs

What is the double circulatory system

One side pumps to the body the other side pumps to the lungs

What do artiries have

Thick muscular walls, carry blood away from the heart at high pressure

What do veins have

Thinner walls, carry blood back to the heart, have valves

What do capillaries have

They are tiny, one-cell thick walls for diffusion, high density for gas exchange.

What do waxy cuticles in plants do

Reduces water loss

What does upper epidermis have in plants and what is the function

They are transparent to let light through

What does palisade layer have

Lots of chloroplasts for photosynthesis

what does the spongy mesophyll have

Air spaces for gas exchange

What does the lower epidermis have

Has stomata and guard cells for gas exchange

What do the xylem and phloem do

Transport water and nutrients around the plant